Black is good worth uba tuba go for it.

Black would be fine, stainless steel too.
The best would be the color that sparkles your uba tuba granite though. Do you have yellow, green or grey in your uba tuba granite? If you pick this complementary color, then it would help the countertop to sparkle even more and would make it easier the addition of colors in your kitchen if you decide to do so at some point.

I'm getting green uba tuba, very dark. I was thinking it would make the faucet, which will be high arc and extend well above the backsplash, sort of blend in. But maybe I want it to shine instead

You need to think about which effect you would like the faucet to give.
Black, green or shiny should work fine here. Black would make the faucet a little less noticeable, green would make it pop more and shiny even more. It depends of what else you have in the room too. What is the color of the kitchen island, cabinetry, walls etc... So really what you would like the faucet to bring to the room is the most important here.

You can get black chrome if you like it. Shiny black chrome

also depends on what backsplash you have- a black faucet will show up fine against a lighter one, chrome feels more modern. I think I'm getting Ubatuba and I went with chrome for contrast.